1. Field of the Invention
This invention concerns the use of a high molecular weight polyalkylmethacrylate to reduce the pour point of a wax isomerate.
2. Description of Related Art
The addition of polyalkylmethacrylates to lubricating oils is known. For example, U.S. Pat. No. 2,628,225 discloses that polyalkylmethacrylates can be used as VI improvers and pour point depressants in lubricating oils. In addition, U.S. Pat. No. 4,968,444 discloses that the pour point of a lubricating oil can be reduced by adding a mixture of acrylate or methacrylate polymers. Each polymer contains several acrylate or methacrylate esters. The molecular weight of both polymers ranges from 50,000 to 500,000. More recently, U.S. Ser. No. 630,466 discloses that the pour point of a wax isomerate can be reduced by using a combination of low and high molecular weight polyalkylmethacrylates.
However, these disclosures do not suggest reducing the pour point of a wax isomerate using the particular high molecular weight polyalkylmethacrylate described below.